If we’re being honest, most of us enjoy sweet-tasting things – the occasional soft drink with a meal, or a sweet treat after dinner. Most traditional sweets are laden with sugars, which we’ve been told to avoid at all costs. So in order to get a sweet fix – many of us have turned to ‘diet’ products. Think diet cola, diet chocolate mousse, diet jelly, diet yoghurt. Many protein shakes and bars also use artificial sweeteners.

The question we’re asking is, are sugar-free desserts and supplements a good alternative? Or are ‘fake sugars’ more harmful than the real thing?

In order to answer this question, let’s review the facts:

What are they?

Added sugars: The most common sugars added to foods include sucrose (i.e. table sugar, coconut sugar, maple syrup), fructose (i.e. fruit extracts, honey), and glucose (i.e. rice malt syrup).

These sugars provide energy, approximately 16kj per gram. Most of these added sugars have a moderate to high glycaemic index – they are digested quickly into glucose, causing spikes and drops in our blood sugar levels. This is particularly problematic for people with impaired glucose tolerance or diabetes.

The Heart Foundation (1) recommends that added sugars should be restricted to less than 10% of your total energy intake – this is about 7tsp within a daily intake a 8,700kJ (i.e. 2,000cal).  About 80% of the added sugars you consume each day are in packaged foods. A flavoured yoghurt, for example, may have 2-3tsp of added sugar per serve!

Artificial sweeteners: Artificial sweeteners are described as containing 0kJ, or as being ‘calorie-free’.

Some are produced synthetically, including saccharin, aspartame, acesulfame potassium and sucralose. Others are extracted from natural sources, including stevia and sugar-alcohols (i.e. sorbitol, erythritol and xylitol). Most artificial sweeteners are at least 200 times sweetener than ‘real sugar’.

Ten artificial sweeteners, including those listed above, have been approved to be safe for human consumption by Food Standards Australia New Zealand (the regulatory body for food additives in Australia) (2). The recommended ‘upper limit’ of artificial sweeteners is 5mg per kilogram of body weight, for example, 3g in a 60kg person (3). This equates to 10 large cans of diet coke.

What are some of the benefits?

Added sugars: There are no real health benefits of consuming added sugars.

Artificial sweeteners: They do not erode tooth enamel. In fact – xylitol has been shown to actively improve dental health, by preventing plaque formation. Furthermore, they do not affect blood glucose levels, allowing people with impaired glucose tolerance or diabetes to enjoy sweet tasting foods safely.

What are some of the consequences?

Added sugars:  Multiple studies have linked increasing intakes with obesity, heart disease, diabetes, some cancers, mental health disorders, dental caries and poor gut health (4). Likewise, lowering your intake of added sugars can reduce your risk of these outcomes.

Artificial sweeteners: Emerging studies have shown that consuming synthetic artificial sweeteners may alter gut bacteria, and in turn, impair glucose tolerance in some people. However, the people in these studies were given the ‘upper limit’ of artificial sweeteners to take each day – far more than the average person would consume (3,4). It is uncertain if smaller intakes in humans will have similar consequences. It is also uncertain if naturally occurring sweeteners, including sugar alcohols and stevia, have the same effect.

Animal studies have found that the consumption of artificial sweeteners may increase hunger (4), but this has yet to be replicated in humans.

Do artificial sweeteners assist with weight loss?

Artificial sweeteners are very low calorie, and therefore, it’s reasonable to assume that replacing sugars with artificial sweeteners will assist with weight loss. However, studies looking at synthetic sweeteners have failed to demonstrate this theory. In fact, some studies have shown that users of synthetic sweeteners are more likely to be overweight than non-users (4). This may be because users of synthetic sweeteners enjoy sweet tasting foods, and are more likely to indulge in ‘real sugars’ as well. Furthermore, some people who use synthetic sweeteners see this ‘good’ behaviour as an excuse to indulge in other ways. Possible changes in gut bacteria, as discussed above, provide a third hypothesis.

There are no studies looking at the long term weight outcomes for stevia or sugar alcohols (6).

Do artificial sweeteners cause cancer?

The Cancer Council of Australia has reported that artificial sweeteners do not cause cancer. This decision has been determined after analysing a large number of quality scientific studies and experiments (5).


Although artificial sweeteners have some clear health benefits over added sugars, they may not entirely ‘guilt free’ – particularly in the case of synthetic varieties. This is especially true if they cause an increase in your sweet cravings and appetite! And – we probably haven’t learned all there is to know about the long term safety of all types of artificial sweeteners. Although yet to be proven, new hypotheses linking artificial sweeteners and health consequences are popping up by the day.

Our recommendation?

The best option will always be unsweetened varieties. For example, buying an unsweetened, natural yoghurt. You can sweeten this in a natural, healthy way using fresh, frozen or stewed fruits. Another example – drinking your coffee and tea straight up, or with a dash of milk, instead of adding sugar or sweetener.

However, if you enjoy the taste and convenience of pre-sweetened options, and you consume these products regularly, we recommend an artificially sweetened options. Preferably, a product that uses stevia or a sugar alcohol – as these have less ‘negative’ press. For example, Danone YoPro is a yoghurt that uses stevia rather than added sugar or synthetic sweeteners. Likewise, adding stevia to your beverages.

If you indulge in sweets very occasionally, a little ‘real sugar’ should be fine.